Grinding wheel dresser



July 19, 1932- J. A. DAVENPORT GRINDING WHEEL DRESSER Filed Jan. 5. 1931 Patented July 19, 1932 UNITED STATES JOHN ADRIAN DAVENPORT, F BUTTE, MONTANA GRINDING WHEEL DRESSER r Application ledanuary 3,71931. y Serial No. 506,475'.

This invention relates to a machine, or' an attachment for use with a grinding machine, for trueing or dressing grinding wheels. The dressing machine or attachment is gen- `l erally applicable to grinding machines employing one or more grinding wheels in the form of combinations of frustrums yofy right cones, or of frustrums of cones and cylinders.

As will be apparent from the following specification, the invention may be employed for dressing a single grinding wheel, but it is particularly useful in the dressing of grinding wheels set in gangs. In trueing H grinding wheels set in gangs, it is difficult to Mao finish the active faces of all units exactly to the desired shape and the proper relative position with respect to each other `and to the work when a single dressing tool is moved successively into engagement with the several grinding surfaces.

An object of the invention is to provide a dressing machine which includes a separate dressing wheel for each of the'active grind- Y ing surfaces of one or more grinding wheels.

A further object is to provide a dressing machine in which a plurality of dressers are carried by a single holder block which slides upon a fixed base, guiding elements being provided. for constraining the holder block to move along such a path that the dressers are all properly presented to and moved along the respective grinding surfaces which are to be trued. More particularly, an object is to provide a machine of the type stated in 5 which the separate dressers, the holder,'base chine in position adjacent a gangV of grinding wheels,

Fig. 2 is an 'end elevation of the same, and

Fig. 3 is a fragmentary plan view of a single dresser wheel and its holder.

yFor clearness of illustration, the dressers are shown out-of contact with the wheels in each of the views.

AIn the drawing, the reference numerals l1 identify grinding wheels having the form of double frustrums of cones, the conical surfaces 2 constituting the active or grinding surfaces of the wheels. A separate dresser 3 is provided for each grinding surface 2, each dresser comprising a set of toothed, hardened steel cutters of cylindrical form or grinding wheels of cylindrical form. For each grinding surface 2, the dresserwheel 3 ismounted on a pin i that is carried by a holder 5 that terminates in a threaded shank 6.

The several holders are secured in a holder block 7 by nuts 8 on the ends of the threaded sections 6, and the holders haverkeys 9 which enter corresponding grooves, not shown, in holder block 7 to prevent rotation of the holders in the block. u l

The holder block 7 slides upon a frame, or bed plate 10 which has side frame members 11 to which a retainer plate 12 is secured by bolts and nuts 13, the retainer plate engaging the upper face of the holder block 7. `Both the upper and lower faces of the block 7 are provided with a pair of V-shaped guide slots 14, the waxes of the branches of the slots being parallel to the respective grinding faces` 2 of the series of identical grinding wheels 1.

Pins 15 project into the several slots from the adjacent faces of the bed plate 10 and retainer plate 12, wherebyy the application to thev holder block 7 ofa force tending to move the same across the series of grinding wheels constrains the holder block to travel along a path having branches parallel to the grinding surfaces. y

Notched arms 16 extend from the rear face of the holder block 7 and arod 17 extends through the notch in the arms 16 and carries abutmen'ts 18 that bear against the outer faces of the'arms. The rod 17 is threaded in one side frame member 11and slides in the other 'l grinding member, a. handle 19 being provided for rotating the rod to move the holder frame across the grinding wheels.

The bed plate 10 is slidably mounted upon the base 20 for movement in a direction normalto the axis of the shaft carrying the grinding wheels, and is constrained to such path of movement by keys 21 Awhich project into grooves 22 in the base 20. Aithreaded screw 23 is rotatably mounted on the base 2O and extends through a depending lug 24 on the bed plate 10 for moving the bed plate and thereby the dressers toward and from the grinding wheels. The. outer end of the screw preferably carries a large index or micrometer 25 for use in setting the bed plate to the desired position.

lThe base 20 is provided with iianges 26 for securing the apparatus to the bed of a grinding machine at theside opposite that occupied; by the. work piece, or for clamping the apparatus to the grinding machine in place of the work holder during the dressing opera.- tion when it is not convenient to make the dressing apparatus a permanent part of the grinding machine.

As indicated in Fig. 2, by the broken line representations of two grinding wheels'. 1 and 1'al of different diameters, the dressing apparatus will operate effectively upon the grinding wheels from the time of the installation of new wheels until the grinding wheels are worn down so far asto necessitate replacement. The placing of the dresser wheels at different elevations, see Fig. 2, permits a more compact and rugged construction than would beY possible if all of the wheel holders 5 were at the same level.

The dressing operation is effected byrst adjusting the micrometer dial 25V to place the bed plate 10 at the proper distance from the axes. of the grinding wheels, and then rotat- :ing the handle 19 to move the holder "blocky across the set of grinding wheels.

'As they holder block is translated: bythe rod 17, the transverse. movement resulting from the guiding action of slotslll and' pins 15-is permitted by the grooves in the arms 16 onj the holder block. The holder block thus carries 'each series of dressers ina path parallel to the adjacent grinding surfaces, vthe dressing of all grinding surfaces. at-the right side of the wheels taking place. alternately with the dressing of surfaces at the left of all of the grinding wheels.

Attention-is directed to the fact that the machine may be quickly taken apart to substitute other parts if one proves detective, or to adapt the machine for the dressing of other forms or arrangements of grinding Wheels. By replacing the holderblock by Y another having grooves of different shape,

the machine may be altered to function. properlywhen another set of grinding wheels is substituted on. the` grinder, or to dress the wheels on another grinder when the dresser is to be employed with a plurality of grinders. Similarly, a block having another spacing of the sockets for receiving the individual dresser holders may be substituted if the axial spacing of the grinding wheels is to be changed. lVhfen the dressing machine is a permanent part of the grinding machine,

vthe wheels may be dressed without interrupting the grinding operations, or the dresser may be taken apart for inspection or repair while the grinder remains inv operation.

It is thereforey apparent that the invention is not limited to the particular embodimentlhereindescribed as many changes which may be. made; in the. several parts their relative. sizegshapeand location fall with-in the spirit of my invention as set forth. in the following claims. Y rEhe gauged grinding wheels may be of truste-.conical form, as shown in the drawing, or may include cylindrical and/or radial aswell as conical grinding surfaces. vIn thercase of Combinations including radial grindingA surfaces, the axis of the translating feed screw must lie at such angle to the4 axis ot the grinding wheels that the guide pins will move along those branches ot the guide slots which lie normal to thev axis ot the grinding wheels.

I claim: Y

1. In a grinding wheel dressing machine adapted to dress a grinding Wheely having a vplurality of faces,. a dresser for each grinding wheel face, a movableholder block adapted to. support said. dressers` against. relative movement, and. guide means for said holder block, to. constrain the same to a path of movement effective to guide each dresser over its corresponding` grinding wheel face.

2. Inv a. grinding wheel Vdressing machine adapted. to dress a grinding wheel having a plurality of faces, a dresser. for each. grinding wheel face, a holder block adapted to support said dresse-rs, ay plate on which said block slides, a slot inv said holder block havling` the,y same: contour as thegrinding wheel,

block having the same contour as they grindin-g wheel, apin'associated with'saidv slot and lixed to said plate, andmeans to move said' holder' block across the'grinding wheel.

4f. The device as set forth in claim 3, in combination with means' for adjusting the said plate perpendicular to the axis of the grinder.

5. In a machine for dressing a plurality of grinding wheels, all of said wheels having identical profiles and each of said wheels having active grinding portions constituted by at least two different surfaces of revolution; a cylindrical dresser for each of said conical surfaces, a holder supporting each dresser for rotation with its axis parallel to the line of contact between the dresser and its associated grinding Wheel, a holder block in which all of said holders are rigidly fixed, a bed plate slidably supporting said holder block, and means for moving said block upon said plate to carry each dresser across the face of its associated grinding wheel.

6. The invention as set forth in claim 5, wherein said means for moving said block comprises means for imparting to said block a force tending to move the same parallel to the axes of said grinding wheels, 'and guide means constraining said block to move parallel to the axes of said cylindrical dressers.

7. The invention as set forth in claim 5, in combination with a base supporting said bed plate, and means for adjusting said bed plate towards and from the grinding Wheels.

8. The invention as set forth in claim 5, wherein the holders for the dressers cooperating with one set of grinding surfaces are mounted on said holder block in a line parallel to the axes of the grinding wheels, and the holders for another set of dressers are mounted in line parallel to but spaced from the line of said first holders.

9. In a machine for dressing a plurality of grinding wheels of identical shape and each of which has the form of a double frustro-conical body; a cylindrical dresser for each conical grinding surface, a holder for each dresser and upon which the dresserr is mounted for rotation with its axis parallel to the line of contact between the dresser and its associated grinding Wheel, a base, and means rigidly supporting said holders upon said base for movement to carry the respective dressers in lines parallel to their respective axes while the said dressers engage their associated grinding wheels.

10. The invention as set forth in claim 9 wherein the holders for the dressers cooperating with one set of frustro-conical grinding surfaces are mounted on said holder block in a line parallel to the axes of the grinding wheels, and the remaining holders are mounted in line parallel to but spaced from the line of said first holders.

11. The invention as set forth in claim 9, wherein said supporting means comprises a bed plate carried by said base and supporting said holder block, means for sliding said holder block upon said bed plate, and guide means constraining said holder block to 

